Conventional elevator systems utilize limit switches disposed on each floor inside an elevator hoistway. Each limit switch comprises a box-like enclosure and an arm. The arm further comprises a cam follower mounted on a spindle. As an elevator car reaches a certain floor, a cam disposed on a side of the elevator car comes into a contact with the cam follower to move the arm. The limit switch is activated by the arm movement to send a signal to a computer to let it know the exact location of the elevator cab at that particular time.
The cam followers are repeatedly impacted and must withstand much abuse. The cam followers are typically fabricated from either foam or hard rubber. The cam followers may also include a roller bearing or a similar device to absorb the impact of the elevator cam and to resume its original shape.